Analysis of structural factors related to spectroscopic data and redox potentials of CuT1 models through DFT tools

Six complexes, mimics of T1 Cu active site, were studied under the density functional theory framework and their redox potentials were theoretically estimated with an average error of 0.095 V. Among different functionals, the hybrid functional PBE0 gave the best results to reproduce geometric parameters and to estimate redox potentials. The use of computational methods allowed the identification of relevant structural factors to rationalize spectroscopic and redox potential measurements. The inclusion of explicit molecules of solvent (tetrahydrofurane) showed that only those complexes with net positive charge exhibit coordination with the solvent. The consideration of such interaction permits the correct estimation of redox potentials. When the equilibrium between possible coordination isomers of T1 Cu models is taken into account, a reinterpretation of spectroscopic data (EPR and UV-vis) is possible. These equilibria are governed mainly by entropic contributions and the solvation energy. (C) 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2012